polar coordinate system

1. A system of coordinates in which the location of a point is determined by its distance from a fixed point at the center of the coordinate space (called the pole) and by the measurement of the angle formed by a fixed line (the polar axis, corresponding to the x -axis in Cartesian coordinates) and a line from the pole through the given point. The polar coordinates of a point are given as ( r , θ ), where r is the distance of the point from the pole, and θ is the measure of the angle.
2. Compare Cartesian coordinate system